100mm Dia. ER32 Collet chuck mounted on spindle,opinions?

Ken,

I see you have already ordered a chuck from Amazon, but I will throw this out there anyway as food for thought.

Some of the chucks that mention backplates also show back recesses in the pics or on the drawing of the chuck, so they can be direct mounted to a corresponding size spindle without a backplate. I don’t see where you say what lathe it’s going on, but a 100mm chuck should be a direct mount on a 100mm/4” spindle. If it’s a different size spindle, it will need a backplate.

Some of the ER chucks pictured on Amazon don’t show any tommy bar holes in the flange of the chuck to back up the wrench when tightening or loosening the collet nut. On my LMS bench lathe, there is no way to lock the spindle, so a tommy bar is a must. FWIW, the pic of the LMS chuck does show tommy bar holes.

Lastly, I have an ER-32 chuck and set of collets, but I wish I had been smart enough to go with ER-40 even though my spindle won’t pass stock that large. With an ER-40 setup, I could at least turn short pieces of 1” stock without changing chucks, and even long pieces with a tailstock center. If you want to consider an ER-40 set up, I have found Amazon to be very accommodating for exchanges and refunds.

Hope these thoughts are helpful and aren’t too late.

Tom

Tom, great post. I never noticed the holes for the Tommy Bar until you mentioned it, I guess I will have to drill the holes myself .thanks for bringing it to my attention..
The lathe I bought this chuck for, is a mini lathe (LMS 5200) , bought the HIPP chuck hoping it will be a direct mount but in case it's not,I already have a back plate( bought it when I ordered the lathe) ,so I'll be alright either way , just extra time needed to set up and more of a PITA.
You have good point on the larger ER40, I do understand your reasoning behind your preference for the ER40 , my main objective for buying a ER 32 chuck was so I could hold smaller /narrower projects like rods (1/4" or smaller) but I may com to your conclusion at some point in the future.

Tom, out of curiosity, which sizes of collets do you use more often ? or it depends on the project at hand, the reason I ask is, some ER32 sets come in 6 or 12 pieces from 1/8" to 3/4" ,the metric ones go as high as 19 collets per set from 2mm to 20mm. I did buy the chuck for the purpose of workholding ,not tool holding, which makes me think,the more collets of differents sizes, the better.

Ken,

My ER-32 collets range from 3/32” to 3/4” in 1/32” increments. That leaves no coverage gaps. The sizes I use the most (guessing here) are from 1/4” to 1/2” and the 3/4” collet. I have used most all of them at one time or another, except maybe a couple of sizes under 1/4”. I have a 5C chuck and collets for stock from 3/4” to 1”. An ER-40 setup would have been cheaper in the long run, and more flexible for collet sizing than the 5C is, but, hey, hindsight is 20/20. Besides, he who dies with the most toys wins, right?

Tom

BROCKWOOD said:

ER this & ER that. I honestly don't know what all I have. 1 set is for an R8 shank drive but I use MT3 & finally went to direct mount collets in my little mill. Grizzly does not state what ER version any of them are. I have been watching & see that ER collet holders mounted in a lathe spindle are superb. When I do get to the point of needing collets in my lathe spindle: I'll be using 5C. Might be a fun project!

Click to expand...

If you have the most common Grizzly collet chuck and collet sets, they are not ER anything, they are according to one of their techs, a Din #6388 series collet chuck and collets.


PS: the collets are either EOC 25 or SYOZ 25 (different nomenclature, but same collets)

I recently bought a 100mm HHIP ER-32 collet chuck. I carefully made my own back plate, since I have a L00 spindle lathe.
It appears that it is close to 0.001" out of concentricity, from the back recess to the collet area.
I plan on reducing the backplate snout a bit and attempting to shim to get it closer to zero TIR...

I have a Sieg C3, 7" x 14", mini lathe. It came with a standard 80mm 3 jaw chuck, which is o.k., not great but o.k. I also have a direct flange mounting ER32 collet chuck, with a full set of metric (2mm to 20mm) and some imperial collets (1/4",3/8", 1/2" etc). I bought the collet chuck and a few collets when I bought the lathe maybe 12 or 13 years ago. Odd collets have been added since then, mainly from CTC. Yes they are Chinese, but I have found that they are quite consistent, and their total runout is within the stated spec., I think it's 0.009mm T.I.R.. Yes I did check them all!! They also do minimum runout collets which have from memory 0.005mm runout. By the way 0.005mm, is about 0.0002".
The 3J chuck, collet chuck and spindle flange have been marked so they always go back in the same place, with minimum runout. I can't remember what the collet chuck runout was, except that it was a micron or two more than the spindle, and quite acceptable to me, the 3J chuck runout is whatever it says on the spec sheet, but that only gets used for big tolerance tasks, so thats o.k. At a guess I use the collet chuck 80% of the time, the 3J about 19% and the 4J the rest.
If I was going through the same process again from scratch, I would get exactly the same set up.
By the way, I also have a Sieg X2 mini mill, which uses an ER32 chuck with an MT3 spindle fitting. The same set of collets is used in the mill, for toolholding. No problems.
Best of luck!!
cheers
Bill

My experience with the HHIP ER-40 direct mount D1-4 collet chuck was more disappointing, measuring both the chuck collet face and using a precision ground pin, the run out was ~0.004". This was 10X worse then what was stated as the TIR maximum. Nice concept if it works, but the QC is poor. I also spoke directly with the company, they are just an importer, and what I was told they do not have the means to check anything. So it was returned. I contemplated machining a D1-4 back plate and mounting either a plain back 125mm ER-40 chuck with a machined set-tru setup or mounting a another type of ER-40 chuck with a straight extension/flange to the back plate. In the end, I just used a 5C collet system with a Set-Tru chuck. As a side note, before I went to a Set-Tru 5C chuck, I returned two inexpensive D1-4 mount 5C chucks because their TIR was in the 0.006-0.008 range. Even worse than my experience with the ER-40 direct mount chuck.

There are some fundamental differences between an ER collet system and a 5C, these has been extensively discussed in previous posts. ER collets for the most part have marginally better TIR then 5C, and have a greater compressibility range. Generic ER sets specify a maximum TIR ~0.0004, better ones like Teckniks are 0.0002", my 5C set is ~0.0004". But in practice the TIR suffers and so does the holding power as one gets toward the limits of each collet's compression range. I became aware of this with my ER collets when using my edge finders which have 10 and 12mm shanks, and trying to hold them with a fractional sized ER collet. I also have a 1/32 increment set of ER-40 collets, which has a better overlap then using a 1 mm increment metric set. I have also seen this reported in other postings specific to the 1 mm increment collet sets that are suppose to cover fractional inch sizes, in most cases they had problems but it could have been the quality of the ER set. So my recommendation is go with a 1/32 ER collet set if you are going to use it to hold stock. The problem is that sellers don not sell "complete" ER collet sets in 1/32" increments, there always seems to be a few that they leave out. So I purchased a Z-Live 1/32 ER-40 set (23 piece) and back filled the missing ER-40 collets with some made by Techniks, the latter are very nicely made but more expensive. I use an ETM ER-32 collet set on my mill, they have almost unmeasurable run out.

ER collets are designed to hold tooling along the full length of the collet, they are not designed to hold short pieces of stock, and as such the back of the collet can distort if you try to hold something like a 3/4" long rod. The 5C collets are made to hold stock at the tip of the collet, I have held and machined stock as short as 1/4". But because the 5C collets (in particular the smaller sizes) have a very short clamping/holding area, there is less overall holding power and greater tendency for a piece to have more axial skewing. ER collets are designed to have very specific torquing requirements, often this is very hard to achieve unless they are in a fixture and you have the proper torquing wrench. I use bearing nuts on on my ER chucks, they make it a bit easier to tighten/loosen the nut. But I have also had the bearing in the nut fail when compressing an ER collet down to its lower clamping range (1/2" ER-40 collet clamping a 12mm shaft).

An ER system is more versatile than a 5C in that it can be used in a mill, in the lathe tail stock, and as a lathe chuck. Cost wise, a 5C setup requires about twice as many collets to cover the same clamping range and the better 5C chucks can be very pricey. On a smaller lathe or for infrequent use, I probably would say an ER chuck system would be more cost effective, but otherwise my preference for holding small stock in a lathe is for 5C. I use my 5C system about 50% of the time, I use a speed handle for the 5C chuck so it is very quick, and for repeat work with a stop I have found it to be very accurate.

Z-Live set, back filled missing collets with Techniks. Case was rebuilt and modified to hold the additional collets and 12mm collet used for my Haimer edge finder.

Bill, my take is very close to yours. Just curious tho if you have a full set of metric collets why you need any Imperial ones.
for example, does a 6-7mm collet not hold a 1/4'' tool or work?

Unless you plan on doing production work a collet chuck is very limiting with regards to work holding, if you are a hobbyist and every job that you do is different then the last you will quickly realize this.

Hi Tozguy,
The big advantage of having both metric and some imperial collets is simple. Recognising that ER collets hold most accurately at their nominal "free" diameter, if say a 1/4" shank cutter, or a piece of accurate 1/4" bar is to be held, with minimum runout, simply use the 1/4" collet, rather than the 7mm one. Whilst most of my milling cutters are metric, there are quite a few that are imperial, when the same argument applies. However all milling cutters have a "nominal" size shank, 1/4", 1/2" 10mm, 12mm etc
Yes I agree Wreck, however as a hobbyist I frequently make a series of small but different components out of (say) a piece of 20mm bar. I just prefer a collet chuck, when either 3J or collet could be used. Horses for courses I suppose.
cheers
Bill